The present invention is related to a transmission measure of power tool, and more particularly to a transmission member with torque-restricting protective structure.
A conventional power torque tool is applicable to a work piece for wrenching or unscrewing the work piece. The power tool is generally equipped with a torque-adjusting mechanism or torque-restricting mechanism for adjusting/restricting the nominal torque value. Taiwanese Patent No. 092128742 discloses a socket with a nominal torque value. Ratchet wheels and a spring are disposed inside the socket. In the case that an excessively great torque is applied to the socket, the ratchet wheels are resiliently disengaged from each other to protect the work piece.
The socket of the above Patent has some shortcomings. For example, when tightening a work piece, the ratchet wheels cannot be truly disengaged from each other in the case of too great torque. This is because that the ratchet wheels are reversely displaced to disengage from each other. In the disengaged state, the distance between the ratchet wheels is enlarged. Two opposite ends of the ratchet wheels are respectively for coupling with an output end of a power supply and a work piece. Therefore, when the socket is bridged between the output end of the power supply and the work piece for wrenching/screwing the work piece, the distance between the output end of the power supply and the work piece is fixed. Basically, there is no further room for the two ratchet wheels to displace in reverse directions. Therefore, such socket can hardly truly achieve the torque-restricting protective effect.